﻿/*
* Copyright (c) 2010-2012 Tesla Engine Group
* 
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
* 
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
* 
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
* THE SOFTWARE.
*/

namespace Tesla.Graphics {
    /// <summary>
    /// Comparer for the ortho render bucket. This sorts renderables first
    /// by their ortho order. Renderables with smaller ortho order values
    /// are rendered first.
    /// </summary>
    public sealed class OrthoRenderBucketComparer : IRenderBucketComparer {
        private IRenderer _renderer;

        /// <summary>
        /// Creates a new OrthoRenderBucketComparer
        /// </summary>
        /// <param name="renderer">Renderer to use</param>
        public OrthoRenderBucketComparer(IRenderer renderer) {
            _renderer = renderer;
        }

        /// <summary>
        /// Compares two renderable's by their ortho order property. If
        /// x is less than y, -1 is returned. If x is greater than y, 1 
        /// is returned. If they're equal then 0 is returned.
        /// </summary>
        /// <param name="x">First renderable</param>
        /// <param name="y">Second renderable</param>
        /// <returns>Comparision result</returns>
        public int Compare(IRenderable x, IRenderable y) {
            if(x.OrthoOrder == y.OrthoOrder) {
                return 0;
            } else if(x.OrthoOrder < y.OrthoOrder) {
                return -1;
            } else {
                return 1;
            }
        }
    }
}
